Burned area
satellite only34,546ha
Perimeter published by GWIS (Copernicus).
- Source
- GWIS (Copernicus)
- Date
- 2 Sept 2025 – 16 Sept 2025
+− cross-check
No official record is matched to this page to compare it with.
ZM · Zambia · –
Kasempa fire, 2 September 2025 Mufumbwe
Out · last detection 16 Sept 2025, 11:59 UTC
The fire started on 2 September 2025 in Kasempa, Zambia, and satellites saw it burning for 15 days. Copernicus’s global GWIS system rebuilt a burnt perimeter of 34,546 hectares from heat detections, spread across a single municipality.
Number 14 in Zambia in 2025, of 257.
GWIS near-real-time perimeter, from the layer that changed in August 2025: this fire is not compared with fires from earlier years, because since then the GWIS layer gives more and larger perimeters.
Use this data
Compare with…
Use this data
Fire page data · version 2026-11-15matches the official recordwith caveatssatellite onlymodel
When copying, the sentence is
Tick the figures you want: they make up the lede and the CSV.
Duration by satellite
satellite only15days
2 Sept 2025 to 16 Sept 2025: first and last day with fire on the page.
- Source
- GWIS (Copernicus) · NASA FIRMS · VIIRS
- Date
- last detection: 16 Sept 2025, 11:59 UTC
+− cross-check
Satellites pass a few times a day and cloud or smoke can hide the fire: a lack of detections is not an official extinction. Each country’s emergency service declares a fire contained or out.
Start
satellite only2 Sept 2025
First day with fire seen by the satellites or the perimeter.
- Source
- GWIS (Copernicus) · NASA FIRMS · VIIRS
- Date
- 2 Sept 2025
+− cross-check
No official record is matched to this page, so the alert time and the cause are not known here.
Hotspots
satellite only1,110
VIIRS detections at 375 m. Most intense hotspot: 259 MW.
- Source
- NASA FIRMS · VIIRS (Suomi NPP)
- Date
- 2 Sept 2025 – 16 Sept 2025
+− cross-check
There is no official record to compare with. Each hotspot is a pixel detected in one satellite pass, not a separate fire.
The worst day
satellite only2,716MW
Total radiative power on 5 September 2025; hotspots that day: 137.
- Source
- NASA FIRMS · VIIRS (FRP)
- Date
- 5 Sept 2025
+− cross-check
Fire radiative power (FRP) measures the energy the fire gives off when the satellite passes. Added up by day, it compares intensity, not area.
Danger at the start
model79.9FWI · very extreme
Fire Weather Index (Canadian system) computed by WorldFires for the day the fire started. Consecutive days without rain before: 60.
- Source
- WorldFires calculation (Canadian FWI system)
- Date
- 2 Sept 2025, local noon
- Model
- ERA5 0,25° (ECMWF · Copernicus C3S) · Open-Meteo.com
+− cross-check
This is an index computed from weather model data, not a measurement of the fire nor an official warning. Danger warnings are issued by each country’s authority. Emergency number and official warnings
Weather during the fire
model35.1°C · 10% RH
High of 35.1 °C and minimum humidity of 10% on 16 September 2025; gusts of 52 km/h on 2 September 2025.
- Source
- weather model at the fire’s grid cell
- Date
- 2 Sept 2025 – 16 Sept 2025
- Model
- ERA5 0,25° (ECMWF · Copernicus C3S) · Open-Meteo.com
+− cross-check
These are model values for a cell of about 25 km, not from a weather station: they may differ from what was measured on the ground.
This page’s change log has been kept since 24 October 2026: every night what it publishes is compared and the difference is logged. Anything earlier is reconstructed from each source’s date and marked as reconstructed.
Show
-
logName: Mufumbwe → Kasempa.
-
· reconstructed weatherWeather and FWI computed from the ERA5 reanalysis
-
logLast day with fire: 13 September 2025 → 16 September 2025.
-
logStart date: 3 September 2025 → 2 September 2025.
Area logged each night
Move the slider to see which area the page published each day.
Versioned permanent link
https://worldfires.org/en/fire/kasempa-2025-09-4?v=2026-11-15A version keeps the area, dates, name and official record; the area as it was logged (changes under 2% are not logged). The map, hotspots and weather always show today’s data.
Citation
A lede of about 60 words figures only, no adjectives
CSV for this fire kasempa-2025-09-4.csv · daily, no individual hotspots
| fecha | focos_viirs | frp_mw | tmax_c | tmin_c | hr_min_pct | viento_max_kmh | racha_max_kmh | precip_mm | fwi | clase_fwi | dentro_del_incendio |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2025-09-02 | 31 | 560 | 30.2 | 12.9 | 11 | 21.6 | 52.2 | 0 | 79.9 | muy_extremo | 1 |
| 2025-09-03 | 147 | 2,042 | 29.9 | 14.5 | 17 | 16.8 | 41.4 | 0 | 62.8 | extremo | 1 |
| 2025-09-04 | 194 | 1,203 | 31 | 14 | 14 | 17.7 | 43.9 | 0 | 64.9 | extremo | 1 |
| 2025-09-05 | 137 | 2,716 | 31.8 | 12.8 | 15 | 17.3 | 43.2 | 0 | 63.5 | extremo | 1 |
| 2025-09-06 | 114 | 1,196 | 32.6 | 12.4 | 12 | 12.5 | 31.7 | 0 | 53.2 | extremo | 1 |
| 2025-09-07 | 63 | 656 | 33.6 | 15.5 | 12 | 15.2 | 37.4 | 0 | 56.6 | extremo | 1 |
| 2025-09-08 | 133 | 732 | 33.3 | 16.1 | 12 | 15.6 | 38.9 | 0 | 58.7 | extremo | 1 |
| 2025-09-09 | 180 | 1,742 | 32.9 | 16.3 | 11 | 18.1 | 43.9 | 0 | 70.1 | muy_extremo | 1 |
| 2025-09-10 | 72 | 1,234 | 32.4 | 15 | 16 | 17 | 41.8 | 0 | 58.2 | extremo | 1 |
| 2025-09-11 | 32 | 230 | 32.5 | 16 | 19 | 12.7 | 33.8 | 0 | 51.9 | extremo | 1 |
| 2025-09-12 | 3 | 13 | 32.5 | 17.2 | 22 | 15.1 | 38.2 | 0 | 54.9 | extremo | 1 |
| 2025-09-13 | 1 | 5 | 30.8 | 18.6 | 20 | 15.7 | 38.9 | 0 | 49.6 | muy_alto | 1 |
| 2025-09-14 | 0 | 0 | 34.2 | 17.5 | 12 | 12.2 | 31.3 | 0 | 55.6 | extremo | 1 |
| 2025-09-15 | 1 | 1 | 34.6 | 14.2 | 9 | 12.8 | 34.2 | 0 | 59.4 | extremo | 1 |
| 2025-09-16 | 2 | 13 | 35.1 | 13.7 | 10 | 14.8 | 37.8 | 0 | 70.6 | muy_extremo | 1 |
| 2025-09-17 | 0 | 0 | 35.7 | 15.7 | 10 | 12.9 | 33.8 | 0 | 59.4 | extremo | 0 |
| 2025-09-18 | 0 | 0 | 35.4 | 16.4 | 13 | 19.8 | 47.9 | 0 | 80.2 | muy_extremo | 0 |
| 2025-09-19 | 0 | 0 | 33.6 | 18.6 | 16 | 20.7 | 49.3 | 0 | 73.7 | muy_extremo | 0 |
| 2025-09-20 | 0 | 0 | 33.5 | 21.1 | 22 | 20.5 | 51.1 | 0.1 | 63.1 | extremo | 0 |
| 2025-09-21 | 0 | 0 | 32.7 | 19.1 | 18 | 17 | 42.5 | 0 | 57 | extremo | 0 |
| 2025-09-22 | 0 | 0 | 34.1 | 18 | 18 | 15.1 | 38.5 | 0 | 50 | extremo | 0 |
| 2025-09-23 | 0 | 0 | 35 | 20.4 | 16 | 15.5 | 38.9 | 0 | 55 | extremo | 0 |
| 2025-09-24 | 0 | 0 | 35.6 | 19.1 | 11 | 17.8 | 43.9 | 0 | 56 | extremo | 0 |
| 2025-09-25 | 0 | 0 | 35 | 21.1 | 12 | 16.9 | 41.8 | 0 | 59.1 | extremo | 0 |
| 2025-09-26 | 0 | 0 | 34.6 | 20.5 | 14 | 18.8 | 44.6 | 0 | 65.8 | extremo | 0 |
It is generated in your browser from this page’s data: one file per fire, aggregated by day and without individual hotspots.
Live widget for your story
It updates itself while the fire is still active and links to this page. Free, with the attribution shown at the bottom.
Sources for this page: GWIS (Copernicus), NASA FIRMS (VIIRS), ERA5 (ECMWF/Copernicus C3S) · Open-Meteo.com (CC BY 4.0). Open-Meteo.com · How we build fire pages: methodology
- Burnt area
- 34,546ha
- GWIS perimeter (Copernicus)
- Duration
- 15days
- 2 Sept 2025 – 16 Sept 2025
- Municipalities hit
- 1
- districts
- Started on
- 2 Sept
- 2025
- Heat detections
- 1,110
- in a single hotspot: 259 MW
- Danger at start
- 80
- Very extreme · FWI index
- Average daily power
- 882MW
- detected power per day, on average
Where it burned
HOTSPOTS BY DAY
2 Sept16 Sept
16 Sept 2025
How it evolved, day by day
2 Sept
5 Sept
8 Sept
11 Sept
15 Sept
Fire radiative power detected each day, in megawatts, and number of hotspots. The magenta bar marks the peak day.
The weather it burned in
35°high
52km/h · peak gust
9%lowest humidity
It had gone more than two months without rain (1 mm or more) when it started.
This area had burned before
90% of the perimeter overlaps earlier fires recorded since 2016: 9,810 ha in 2016, 18,556 ha in 2017, 4,166 ha in 2018, 13,356 ha in 2019, 2,558 ha in 2020, 7,260 ha in 2021, 9,856 ha in 2022, 6,146 ha in 2023, 4,006 ha in 2024. Part of it burned more than once, so the yearly figures add up to more than the 31,007 ha that had burned before.
- 14,282 ha Mufumbwe fire, September 2017 24,460 ha in total; the hectares shown are those it shares with this fire
- 4,556 ha Mufumbwe fire, September 2019 9,232 ha in total; the hectares shown are those it shares with this fire
- 3,018 ha Kasempa fire, August 2019 45,963 ha in total; the hectares shown are those it shares with this fire
- 3,006 ha Mufumbwe fire, October 2022 25,793 ha in total; the hectares shown are those it shares with this fire
- 2,587 ha Mufumbwe fire, July 2021 4,311 ha in total; the hectares shown are those it shares with this fire
- 1,686 ha Mufumbwe fire, July 2022 3,174 ha in total; the hectares shown are those it shares with this fire
- 1,445 ha Mufumbwe fire, September 2018 4,879 ha in total; the hectares shown are those it shares with this fire
- 955 ha Mufumbwe fire, September 2023 12,869 ha in total; the hectares shown are those it shares with this fire
How big is it?
London boundary: geoBoundaries · Office for National Statistics (Open Government Licence v3.0).
Paris boundary: geoBoundaries · Institut national de l'information géographique et forestière (IGN-F) (Etalab Open License 2.0).
Madrid boundary: geoBoundaries · Open Data ESRI, IGN Central Registry of Cartography Area (CC BY 4.0).
Berlin boundary: geoBoundaries · Federal Agency for Cartography and Geodesy (dl-de/by-2-0).
This compares size, not location: both shapes are at the same scale, north up, centred on each other.
What happened to each town
-
34,830 ha1.8 %
Burnt area inside each municipality, from crossing the GWIS perimeter with administrative boundaries. The distance runs from the point marking the centre of each area to the nearest fire: staying a kilometre away does not mean it reached the houses.
The weather day by day
ECMWF ERA5 reanalysis at the fire location, the standard reference for past weather, and the Canadian Fire Weather Index (the same system Copernicus uses), computed by WorldFires from that data. Days after the fire run until the first rain.
Open-Meteo.com (CC BY 4.0) · Copernicus Climate Change Service (ERA5)
Started with Strong wind: 4.2 % of the area in Zambia Very dry air: 4.4 % of the area in Zambia 60 days without rain: 91 % of the area in Zambia
| Day | High | Min. humidity | Peak gust | Rain | Danger (FWI) |
|---|---|---|---|---|---|
| 2 Sept | 30.2 °C | 11 % | 52 km/h | 0.0 mm | Very extreme 80 |
| 3 Sept | 29.9 °C | 17 % | 41 km/h | 0.0 mm | Extreme 63 |
| 4 Sept | 31.0 °C | 14 % | 44 km/h | 0.0 mm | Extreme 65 |
| 5 Sept | 31.8 °C | 15 % | 43 km/h | 0.0 mm | Extreme 64 |
| 6 Sept | 32.6 °C | 12 % | 32 km/h | 0.0 mm | Extreme 53 |
| 7 Sept | 33.6 °C | 12 % | 37 km/h | 0.0 mm | Extreme 57 |
| 8 Sept | 33.3 °C | 12 % | 39 km/h | 0.0 mm | Extreme 59 |
| 9 Sept | 32.9 °C | 11 % | 44 km/h | 0.0 mm | Very extreme 70 |
| 10 Sept | 32.4 °C | 16 % | 42 km/h | 0.0 mm | Extreme 58 |
| 11 Sept | 32.5 °C | 19 % | 34 km/h | 0.0 mm | Extreme 52 |
| 12 Sept | 32.5 °C | 22 % | 38 km/h | 0.0 mm | Extreme 55 |
| 13 Sept | 30.8 °C | 20 % | 39 km/h | 0.0 mm | Very high 50 |
| 14 Sept | 34.2 °C | 12 % | 31 km/h | 0.0 mm | Extreme 56 |
| 15 Sept | 34.6 °C | 9 % | 34 km/h | 0.0 mm | Extreme 59 |
| 16 Sept | 35.1 °C | 10 % | 38 km/h | 0.0 mm | Very extreme 71 |
| 17 Sept after | 35.7 °C | 10 % | 34 km/h | 0.0 mm | Extreme 59 |
| 18 Sept after | 35.4 °C | 13 % | 48 km/h | 0.0 mm | Very extreme 80 |
| 19 Sept after | 33.6 °C | 16 % | 49 km/h | 0.0 mm | Very extreme 74 |
| 20 Sept after | 33.5 °C | 22 % | 51 km/h | 0.1 mm | Extreme 63 |
| 21 Sept after | 32.7 °C | 18 % | 42 km/h | 0.0 mm | Extreme 57 |
| 22 Sept after | 34.1 °C | 18 % | 38 km/h | 0.0 mm | Extreme 50 |
| 23 Sept after | 35.0 °C | 16 % | 39 km/h | 0.0 mm | Extreme 55 |
| 24 Sept after | 35.6 °C | 11 % | 44 km/h | 0.0 mm | Extreme 56 |
| 25 Sept after | 35.0 °C | 12 % | 42 km/h | 0.0 mm | Extreme 59 |
| 26 Sept after | 34.6 °C | 14 % | 45 km/h | 0.0 mm | Extreme 66 |
Before and after, from space
Drag the line to compare the same ground before the fire and after it.
↔
Before · 26 Aug 2025
After · 23 Sept 2025
Sentinel-2 did not pass over on that day. Try another date, or use false colour, which is daily.
If the day is cloudy, change the date: each satellite passes once a day. In false colour the burnt ground looks brown or red.
The smoke
CAMS · CopernicusOn 6 September 2025 the air beside the fire reached 122 µg/m³ of PM2.5. That day averaged 69: 4.6 times the WHO daily guideline (15).
PM2.5 peak122 µg/m³
Days over the guideline14 days
PM10124 µg/m³
Optical depth0.88
WHO 15
1 Sept5 Sept9 Sept13 Sept
Good
Fair
Moderate
Poor
Very poor
Extremely poor
Particles from the Copernicus CAMS model at the centre of the perimeter; these are not measurements in each town. The pale bar is the worst hour, the solid one the daily average.
Open-Meteo.com (CC BY 4.0) · Copernicus Atmosphere Monitoring Service (CAMS)
Detections table · 1,110Every satellite heat detection, one by one, with time, satellite, power and coordinates.
⬇ Download CSV
Times in UTC. Each detection is a 375 m pixel: a large fire yields hundreds per pass.
| Date and time | Satellite | FRP (MW) | Lat | Lon |
|---|
Other fires nearby
- 24,460 haMufumbwe13 September 2017 · 26 days · 8 km away
- 22,416 haMufumbwe18 October 2026 · 9 days · 8 km away
- 25,793 haMufumbwe5 October 2022 · 15 days · 11 km away
- 13,599 haKasempa20 July 2026 · 10 days · 17 km away
- 12,869 haMufumbwe2 September 2023 · 12 days · 18 km away
- 134,611 haMufumbweAugust 2025 · 33 days · 38 km away
Frequently asked questions
- How long did the Kasempa fire last?
- According to the heat detections seen by satellite inside the perimeter, it burned from 2 September 2025 to 16 September 2025 (15 days). The perimeter dates it from 3 September 2025 to 13 September 2025.
- How much area did it burn?
- The perimeter GWIS (Copernicus) rebuilt from heat detections is 34,546 hectares (345.5 km²). It is an estimate: official national figures may differ.
- Which municipalities burned?
- The fire only entered Mufumbwe (34,830 ha, 1.8 %).
- What was the weather like?
- During the fire the temperature reached 35.1 °C, humidity dropped to 9 % and gusts hit 52 km/h. The fire danger index (FWI) reached 80, class Very extreme.
- Where does this data come from?
- From the GWIS (Copernicus) burnt perimeter, NASA FIRMS VIIRS hotspots and the administrative boundaries of Zambia (geoBoundaries). It is not an official report.
Where to verify it
A satellite detection is not an official report. Final figures and the fire’s status are published by each country’s emergency service.
Satellite cross-check
History of this page · 3 Changes in area, dates, name, official record or merged pages, compared every night since 24 October 2026.
- Name: Mufumbwe → Kasempa.
- Last day with fire: 13 September 2025 → 16 September 2025.
- Start date: 3 September 2025 → 2 September 2025.
RSS Changes to this page With cross-checks and a citable version
Does something look wrong on this page?
This page is built from satellite data and official records, and it sometimes gets things wrong: the wrong dates, the wrong town, two fires merged into one, or something that was not a wildfire at all. If you know this fire first-hand (you live nearby, saw it, fought it or reported on it), tell us what really happened and we will check it.
Report an error
How we know this
- Perimeter: GWIS (Copernicus), rebuilt from heat detections rather than mapped on imagery.
- Dates adjusted with the VIIRS detections inside the perimeter, which said 3 September 2025 to 13 September 2025. 1,110 Suomi-NPP VIIRS detections on those dates.
- We have not matched this page with any official record.
- Weather: Copernicus ERA5 reanalysis at the fire location, in cells of about 25 km.
Where this data comes from
The perimeter comes from the Copernicus Global Wildfire Information System (GWIS), which rebuilds it from MODIS and VIIRS heat detections and publishes it under CC BY 4.0. It is not measured on imagery as in Europe, so it is an estimate. Heat detections come from the VIIRS sensors aboard Suomi-NPP and NOAA-20, distributed by NASA FIRMS at 375 m resolution. Municipal boundaries come from geoBoundaries ADM2 (Creative Commons Attribution 4.0 (CC BY 4.0)). The area per municipality is computed by WorldFires by crossing the perimeter with those boundaries, so it may differ from each country’s official figure.